From 51c8ad45ce1f8ab876b791caa5d5376bbee844ef Mon Sep 17 00:00:00 2001 From: Alex Date: Thu, 15 Apr 2021 16:45:15 +0200 Subject: [PATCH] MINOR: sample: converter: Add json_query converter With the json_query can a JSON value be extacted from a header or body of the request and saved to a variable. This converter makes it possible to handle some JSON workload to route requests to different backends. --- doc/configuration.txt | 24 ++++++++ reg-tests/converter/json_query.vtc | 95 ++++++++++++++++++++++++++++++ src/sample.c | 88 +++++++++++++++++++++++++++ 3 files changed, 207 insertions(+) create mode 100644 reg-tests/converter/json_query.vtc diff --git a/doc/configuration.txt b/doc/configuration.txt index f242300e7f..61c2a6dd9c 100644 --- a/doc/configuration.txt +++ b/doc/configuration.txt @@ -15961,6 +15961,30 @@ json([]) Output log: {"ip":"127.0.0.1","user-agent":"Very \"Ugly\" UA 1\/2"} +json_query(,[]) + The json_query converter supports the JSON types string, boolean and + number. Floating point numbers will be returned as a string. By + specifying the output_type 'int' the value will be converted to an + Integer. If conversion is not possible the json_query converter fails. + + must be a valid JSON Path string as defined in + https://datatracker.ietf.org/doc/draft-ietf-jsonpath-base/ + + Example: + # get a integer value from the request body + # "{"integer":4}" => 5 + http-request set-var(txn.pay_int) req.body,json_query('$.integer','int'),add(1) + + # get a key with '.' in the name + # {"my.key":"myvalue"} => myvalue + http-request set-var(txn.pay_mykey) req.body,json_query('$.my\\.key') + + # {"boolean-false":false} => 0 + http-request set-var(txn.pay_boolean_false) req.body,json_query('$.boolean-false') + + # get the value of the key 'iss' from a JWT Bearer token + http-request set-var(txn.token_payload) req.hdr(Authorization),word(2,.),ub64dec,json_query('$.iss') + language([,]) Returns the value with the highest q-factor from a list as extracted from the "accept-language" header using "req.fhdr". Values with no q-factor have a diff --git a/reg-tests/converter/json_query.vtc b/reg-tests/converter/json_query.vtc new file mode 100644 index 0000000000..ade7b4ccb3 --- /dev/null +++ b/reg-tests/converter/json_query.vtc @@ -0,0 +1,95 @@ +varnishtest "JSON Query converters Test" +#REQUIRE_VERSION=2.4 + +feature ignore_unknown_macro + +server s1 { + rxreq + txresp +} -repeat 8 -start + +haproxy h1 -conf { + defaults + mode http + timeout connect 1s + timeout client 1s + timeout server 1s + option http-buffer-request + + frontend fe + bind "fd@${fe}" + tcp-request inspect-delay 1s + + http-request set-var(sess.header_json) req.hdr(Authorization),json_query('$.iss') + http-request set-var(sess.pay_json) req.body,json_query('$.iss') + http-request set-var(sess.pay_int) req.body,json_query('$.integer',"int"),add(1) + http-request set-var(sess.pay_neg_int) req.body,json_query('$.negativ-integer',"int"),add(1) + http-request set-var(sess.pay_double) req.body,json_query('$.double') + http-request set-var(sess.pay_boolean_true) req.body,json_query('$.boolean-true') + http-request set-var(sess.pay_boolean_false) req.body,json_query('$.boolean-false') + http-request set-var(sess.pay_mykey) req.body,json_query('$.my\\.key') + + http-response set-header x-var_header %[var(sess.header_json)] + http-response set-header x-var_body %[var(sess.pay_json)] + http-response set-header x-var_body_int %[var(sess.pay_int)] + http-response set-header x-var_body_neg_int %[var(sess.pay_neg_int)] + http-response set-header x-var_body_double %[var(sess.pay_double)] + http-response set-header x-var_body_boolean_true %[var(sess.pay_boolean_true)] + http-response set-header x-var_body_boolean_false %[var(sess.pay_boolean_false)] + http-response set-header x-var_body_mykey %[var(sess.pay_mykey)] + + default_backend be + + backend be + server s1 ${s1_addr}:${s1_port} +} -start + +client c1 -connect ${h1_fe_sock} { + txreq -url "/" \ + -hdr "Authorization: {\"iss\":\"kubernetes.io/serviceaccount\"}" + rxresp + expect resp.status == 200 + expect resp.http.x-var_header ~ "kubernetes.io/serviceaccount" + + txreq -url "/" \ + -body "{\"iss\":\"kubernetes.io/serviceaccount\"}" + rxresp + expect resp.status == 200 + expect resp.http.x-var_body ~ "kubernetes.io/serviceaccount" + + txreq -url "/" \ + -body "{\"integer\":4}" + rxresp + expect resp.status == 200 + expect resp.http.x-var_body_int ~ "5" + + txreq -url "/" \ + -body "{\"integer\":-4}" + rxresp + expect resp.status == 200 + expect resp.http.x-var_body_int ~ "-3" + + txreq -url "/" \ + -body "{\"double\":4.5}" + rxresp + expect resp.status == 200 + expect resp.http.x-var_body_double ~ "4.5" + + txreq -url "/" \ + -body "{\"boolean-true\":true}" + rxresp + expect resp.status == 200 + expect resp.http.x-var_body_boolean_true == 1 + + txreq -url "/" \ + -body "{\"boolean-false\":false}" + rxresp + expect resp.status == 200 + expect resp.http.x-var_body_boolean_false == 0 + + txreq -url "/" \ + -body "{\"my.key\":\"myvalue\"}" + rxresp + expect resp.status == 200 + expect resp.http.x-var_body_mykey ~ "myvalue" +} -run \ No newline at end of file diff --git a/src/sample.c b/src/sample.c index 7337ba06a9..728c7c76d1 100644 --- a/src/sample.c +++ b/src/sample.c @@ -16,6 +16,7 @@ #include #include +#include #include #include @@ -3689,6 +3690,92 @@ static int sample_conv_rtrim(const struct arg *arg_p, struct sample *smp, void * return 1; } +/* This function checks the "json_query" converter's arguments. */ +static int sample_check_json_query(struct arg *arg, struct sample_conv *conv, + const char *file, int line, char **err) +{ + if (arg[0].data.str.data == 0) { + memprintf(err, "json_path must not be empty"); + return 0; + } + + if (arg[1].data.str.data != 0) { + if (strcmp(arg[1].data.str.area, "int") != 0) { + memprintf(err, "output_type only supports \"int\" as argument"); + return 0; + } else { + arg[1].type = ARGT_SINT; + arg[1].data.sint = 0; + } + } + return 1; +} + +/* Limit JSON integer values to the range [-(2**53)+1, (2**53)-1] as per + * the recommendation for interoperable integers in section 6 of RFC 7159. + */ +#define JSON_INT_MAX ((1LL << 53) - 1) +#define JSON_INT_MIN (-JSON_INT_MAX) + +/* This sample function get the value from a given json string. + * The mjson library is used to parse the JSON struct + */ +static int sample_conv_json_query(const struct arg *args, struct sample *smp, void *private) +{ + struct buffer *trash = get_trash_chunk(); + const char *p; /* holds the temporary string from mjson_find */ + int tok, n; /* holds the token enum and the length of the value */ + int rc; /* holds the return code from mjson_get_string */ + + tok = mjson_find(smp->data.u.str.area, smp->data.u.str.data, args[0].data.str.area, &p, &n); + + switch(tok) { + case MJSON_TOK_NUMBER: + if (args[1].type == ARGT_SINT) { + smp->data.u.sint = atoll(p); + + if (smp->data.u.sint < JSON_INT_MIN || smp->data.u.sint > JSON_INT_MAX) + return 0; + + smp->data.type = SMP_T_SINT; + } else { + double double_val; + if (mjson_get_number(smp->data.u.str.area, smp->data.u.str.data, args[0].data.str.area, &double_val) == 0) { + return 0; + } else { + trash->data = snprintf(trash->area,trash->size,"%g",double_val); + smp->data.u.str = *trash; + smp->data.type = SMP_T_STR; + } + } + break; + case MJSON_TOK_TRUE: + smp->data.type = SMP_T_BOOL; + smp->data.u.sint = 1; + break; + case MJSON_TOK_FALSE: + smp->data.type = SMP_T_BOOL; + smp->data.u.sint = 0; + break; + case MJSON_TOK_STRING: + rc = mjson_get_string(smp->data.u.str.area, smp->data.u.str.data, args[0].data.str.area, trash->area, trash->size); + if (rc == -1) { + /* invalid string */ + return 0; + } else { + trash->data = rc; + smp->data.u.str = *trash; + smp->data.type = SMP_T_STR; + } + break; + default: + /* no valid token found */ + return 0; + } + return 1; +} + + /************************************************************************/ /* All supported sample fetch functions must be declared here */ /************************************************************************/ @@ -4203,6 +4290,7 @@ static struct sample_conv_kw_list sample_conv_kws = {ILH, { { "cut_crlf", sample_conv_cut_crlf, 0, NULL, SMP_T_STR, SMP_T_STR }, { "ltrim", sample_conv_ltrim, ARG1(1,STR), NULL, SMP_T_STR, SMP_T_STR }, { "rtrim", sample_conv_rtrim, ARG1(1,STR), NULL, SMP_T_STR, SMP_T_STR }, + { "json_query", sample_conv_json_query, ARG2(1,STR,STR), sample_check_json_query , SMP_T_STR, SMP_T_ANY }, { NULL, NULL, 0, 0, 0 }, }}; -- 2.39.5